Electrophoresis is the separation of molecules in a fluid or gel using an electromotive force. Capillary zone electrophoresis (CZE) is a specific type of electrophoresis which takes place in a capillary tube. The tube is filled with a conductive fluid, i.e., an electrolyte or buffer. A small amount of the sample to be separated is then introduced into one end of the capillary. A high-voltage, for example 30,000 volts, applied across the electrolyte at the ends of the capillary tube supplies the electromotive force required to separate the sample into its constituent molecules. Once separation of the molecules occurs, an optical detector may then be used to "look" through the tube at the exiting end to see the results of the separation.
A major drawback to CZE is the complexity of the process. The process requires: filling the capillary tube with a buffer or electrolyte, introducing a sample to be separated into one end of the tube, providing an electrical connection to the electrolyte at each end of the tube, providing the required high-voltage across the electrical connection made at each end of the tube, and viewing the results through the tube. Each of these steps is a manual process which requires a trained technician to perform. After preparing the contents of the tube and starting the electrophoresis operation, the technician must then wait until the electrophoresis is complete before stopping the operation and rinsing the capillary tube in preparation for the next operation. It is towards automating the CZE process and other sampling processes, and thereby, reducing the amount of operator intervention required, that the present invention has been developed.